The article deals with the role of Martin Heidegger's anti-Semitism in his concept of fundamental ontology. This analysis is done on the basis of the publication of new volumes of his diaries - “Black Notebooks”. The book by Donatella Di Cesare “Heidegger, Jews and Shoah”, first translated into Russian by AE Cherny and published by the publishing house “Vladimir Dal”, is devoted to the comprehension of this problem. Given the new data from these diaries and from Di Cesare's book, it can be assumed that Heidegger's anti-Semitism is essential to his philosophy and has a long history in European and German intellectual heritage. As a rule, Jews were accused there that they did not accept Christ and became key figures in the modernization of European culture, which undermined its traditions and deprived of creativity. Heidegger creates a new version of anti-Semitism - a fundamental ongological one, which accuses Jews of being the main culprits of the oblivion of existence and preachers of existence. Differentiation of being and being is the main antithesis of Heidegger's ontology, and it is in the context of its analysis that we are talking about the crime of the Jews. This crime actually turns out to be fabrication, since it contains directly opposite charges, so that a Jew is not a criminal because he has committed this or that act, but this act is made criminal because a Jew has committed it. He is accused both of the absence of soil and property, and of the claim to them, both in the formalism and rationalism of faith, and in their absence, both in the desire to keep his blood unmixed, and in the desire to bring the European peoples into a Jew. It is these properties that make Heidegger believe that Jews are not people, but stones, that they do not exist, but represent the worst form of existence, whose existence is not genuine, but borrowed and is a fraud. Heidegger sees the Holocaust as the culmination of modernization caused by a machine civilization of destruction and war, in which the Jews are guilty and for which they self-destruct and destroy Europe and the world. At the same time, the article argues that such an ideology, unacceptable and false, is Heidegger's marginal concept, which is not the key to his ontology, but also cannot be simply removed from his philosophy without the emergence of a gap that will make this philosophy impossible.